(57) A sandwich panel in which a connection profile 21 is provided on at least one edge and co-operates with a tongue 15 on the edge of an adjacent panel. The sandwich panel itself is filled with an insulating material, wuch as foam, and has on opposite faces metal sheets 12, 13, 18, 19. A connection profile 21 includes a web 22, first and second edge flanges 23 and 24, nd third and fourth flanges 23 and 24 therebetween. The fourth flange extends into a recess 33 in the tongue and is spaced from the first flange sufficiently to accommodate a part of th tongue as well as the clamping portion 30 of a clamp 31 which holds th panels against a support member 35.